Antioxidants



Patented Apr. 10, 1945 Philip T. Paul, Nangatuck, Conn United StatesRubb N. Y., a corporation assignor to er Company, New York, of NewJersey No Drawing. Application November 10, 1943, Serial No. 509,771

12 Claims. (01. 260-300) This invention relates to a new class ofantioxidants or age-resisters for organic substances which tend todeteriorate by absorption of oxyen from the air, e. g., rubber or alliedgums, unsaturated, fatty oils, such as unsaturated vegetable oils,essential oils, petroleum oils and their derivatives, such asga'solines, soaps, a1- dehydes, synthetic resins, turpentine,insectisides, such as derris root, cube root and pyrethrum, and thelike.

According to the invention, the organic substances are incorporated witha chemical of the formula R1 where aryl and arylene represent anaromatic radical of the benzene or naphthaleneseries; and R and R1represent separate open-chain alkyl radicals or joined alkyleneradicals. The aryl groups may be further substituted by groups such asalkyl, alkoxy, alkenyloxy, halogen, .tertiary amino, etc.

fonyl chloride in 60 cc. benzene, 20.8 g. piper- Exemplary of suchcompounds are the folg5 lowing:

p-Anilino benzene sulfonyl dimethyl amide p-Anilino benzene sulfonyldiethyl amide p-Anilino benzene sulfonyl piperidide p-(p-Toluidino)benzene sulfonyl diamyl amide CHa-CH:

H: KOH

OHrCHi CH: CHaC 01.11

Pnrrmrron r-Bnouo Bmwzam: Sunrom Pmmmma To a solution of g. p-bromobenzene sulidine was added slowly with cooling. A vigorous reactionensued and it was necessary to add more benzene to keep thereactionmixture fluid. After the exothermic reaction had subsided thebenzene solution was washed with water, then with dilute hydrochloricacid, then with dilute sodium hydroxide and finally with water toneutrality. The benzene was; evaporated and the residue crystallizedfrom alcohol. p-Bromo beno- (p-Anisidino) benzene sulfonyl dimethylamide I m-(p-Chlorophenyl) benzene sulfonyl dibutyl amide 4-anilinonaphthalene sulfonyl (1-) dimethyl amide u p-(p-Dimethyl'amino phenyl)benzene sulionyl dimethyl amide.

These chemicals may be prepared by reacting a halogen substitutedsultonylamide with an acyl derivative of a primary arylamine andsubsequently removing the acyl group by hydrolysis. This is illustratedanilino benzene sulfonyl piperidide, as follows:

Roam-1i OH:

" potassium carbonate, 0.1 g.

in the preparation'of para- Amixtune of 201s.

zene sulfonyl piperidide was obtained man yield; melting point 91-915 0.

PREPARATION P-ACETANILIDO BENZENEZv PIPERIDIDE piperidide, 10.67 g.a'cetanilide, 10.9 g. anhydrous copper and 50 cc. methyl n-hexyl.carbinol as solvent were refluxed with stirring 126%: hours. Themixture was cooled and the liquid separated by decantation.

Dioxane was added and the washed by decantation. The various decantedsolutions were combined and subjected to a steam distillation to removethe organic solvents. v

The material insoluble in the dioxane was leached with water, filteredand'the solid filter boiled with benzene zene filtrate was steamdistilled and the residue from thesteam distillation combined with theresidue from the other-steam distillation.

The p-acetanilido benzene sulionyl piperidide was not isolated in a pureform but was bysolid material again SULFQNYL and filtered. This ben--P-anilino benzene sulionyl.

Pmmrron r-Anmmo Benz!!! Sutrom Prrnmml The combined steam distillationresidues were freed from water and refluxed with 90 g. potassiumhydroxide in 90 cc. water and 375 cc. alcohol. After a 2 hour reflux thesolution was diluted with water to 1000 cc. and filtered. The solidcalre was recrystallized from alcohol using decolorlzing charcoal. oncooling p-anilino benzene sulionyl piperidide separated as light browncrystals melting range 168-171" C. Yield The following example, in whichthe arts are by weight, is given to illustrate the eflecflyeness oi thechemicals as antioxidants in rubber.

mama:

Master batch Pale crepe 100 Zinc oxide 10 Whiting 60 Lithopone 60 Zincsoap of cocoanut oil acids... 0.5 Sulfur 3.0 Tetramethyi thiurammonosulfide 0.15

To a portion or the above master batch, p-anilino benzene sulionylpiperidide was added in the ratiooi 1.0partto lOOpartsrubber. Thestockswerecured25minutesat30 poimdspersquare inch steam. V

g Antioxidant re t mam 1mm. in.

810 1; rec-me The invention may be applied to the preservation of,broadly, natural rubber compositions as well as artificially-preparedrubber compositions, such as polychloroprene, olefin, polr u des,butadiene polymers, modified butadieuc polymers (Bima N and Buna S), andincluding reclaims, and latices of such compositions.

It is also to be understood filling and compounding ingredients may beinder, paste or solution form, or applied in. such forms forincorporation by diiiusion, to the surface of vulcanized or unvulcanizedrubber goods.

Having thus described my invention, what I claim and desire to protectby Letters Patent is:

1. A method of retarding the deterioration of an organic substance whichtends to deteriorate by absorption of oxygen from the air whichcomprises incorporating therein an aryl aminoaryl suli'onylamide or thegeneral formula Aryl-NH-Inlene-SOs-N where aryl and arylene represent anaromatic radical selected from the class consisting of the benzene, andnaphthalene series; and B and R: represent radicals selected Iran thegroup consisting or separate open-chain alkyl radicals, and joinedalkylene radicals.

3. An organic substance which tends to deteriorate by absorption oroxygen from the air containinganarylaminoarylsulionylamldeofthe generalformula a Aryi-NH-arylsneSO:N

where aryl and arylene represent an aromatic radical selected irom theclass consisting oi the benzene, and naphthalene series; and R and R1represent radicals selected from the group consisting oi separateopen-chain alkyl radicals, and joined alkylene radicals.

4. A rubber composition containing an aryl aminoaryl sulionylamide orthe general formula corporated along with the preservative, forexamplainthecaseotmbbeniheremaybeincorpmratedotheracoeleratorasortenemetc.

Thesntioxldantmaybeincorporatedinanytypeoirubbercomposltiomsuchasthoseusedtor automobile tires-and tubes,hose, belting, sheet and thread rubber, rubberized fabrics, molded bootsand shoes, etc., whether vulcanized steam.inhotair,orinthecold by theso-called acid process. The proportion of the antioxidantmy varyiromabout 0.1% to where aryl and arylene represent an aromaticradicalselectedtromtheclass consistingotthe benzene, and naphthaleneseries; and R and R1 represent radicals selected from the groupconsisting of separate open-chain alkyl radicals, and joined allryleneradicals.

5. vA method or retarding the deterioration of an organic substancewhich tends to deteriorate by absorption oi oxygen from the air-whichcomprises incorporating therein a phenyl aminoaryl sulionyldialkylsmide.

6. A method oi retarding the deterioration of an organic substance whichtends to deteriorate by absorption oroxygmn'omtheairwhichcomprisesincorporating therein a 'phenyl aminoaryl sulianylplperidlde.

"I. Amethodotpreservlngarubbereompcsltion 2,373,335 which comprisesincorporating therein a phenyi phenyi aminooi'yl suli'onyl piperidide.

11. An orianic substance which tends to-deteriorate by absorption 01'oxyzen from the air con- 5 taming a phenvi aminoaryi suii'onyipiperidide.

12. A rubber composition containing a, phenyl aminoaryl sulfonyipiperidide.

'1. PAUL.

tion which comprises incorporating therein a

